NOTE: This post is Part 5 in my month-long deep dive into exploring "expertise and authority." Get the whole series (as it progresses) here.


Sally Clark had a life that many people would think of as ideal. The daughter of a police officer and a hair dresser in the UK, Sally grew up, went to University, and eventually became a Solicitor in the UK justice system—the equivalent of being a lawyer in the US. She also married another Solicitor, Steve Clark, and together they joined a prestigious law firm in Manchester. But beyond her career, the big accomplishment in her life was her son, Christopher. 

Which was why it was such a blow to Sally and her husband when young Christopher died as a result of sudden infant death syndrome (SIDS), sometimes called "crib death" in the US, or "cot death" in the UK. Sally and her husband had rushed young Christopher to the hospital upon discovering that he wasn't breathing, but it was too late. Their precious boy was gone.

A year later, however, Sally and Steve were blessed with another son, Harry Clark, who was born prematurely but seemed to be doing well. Their grief was still fresh from the loss of Christopher, but they could take joy in the birth of Harry.

And then, against all odds, Harry also died from SIDS, and the grief started all over. 

Worse—not only had they now lost their two precious children, but they were both arrested under suspicion of murder, and eventually Sally herself was convicted of murdering both of her sons in their crib.

She was convicted and sent to prison based largely on the testimony of Professor Sir Roy Meadow, a former Professor of Pediatrics at the University of Leeds.

Painting by numbers

Meadow testified that the chances of two children from an affluent home, with two non-smoking parents,  both dying from SIDS just a year apart were "1 in 73 million."

To put that in perspective, the chances of dying in a terrorist-related airplane crash are 1 in 25 million. The chances of any given American becoming President of the United States are 1 in 10 million. And the chances of dying in the bathtub are 1 in 840,000. All of these are, according to Meadow, more likely than two kids dying suddenly of crib death, just a year apart.

To get to this number, Meadow did something perfectly logical. He took the odds of it happening to one child (1 in 8,543, according to his own calucations) and squared it (8,543 x 8,543 = 75 million). And the jury, aware of Meadow's prestige, his royal title, and his years of expertise, logically accepted those astronomical odds. They rendered a verdict of guilty after a 10-2 majority vote. Case closed.

The problem is, Meadow got the math wrong.

There are a lot of reasons why this number wasn't accurate, but to simplify things let's look at just one major contributor. Meadow had calculated that the odds of one child dying of SIDS under the care of affluent parents was 1 in 8,543—a number that Professor of Mathematics Ray Hill of Salford University says is inaccurate because it fails to account for factors such as the sex of the children. Male children are statistically at greater risk of dying from crib death than girls. This would have influenced the probability by at least half.

In addition, some of the contributing factors that Meadow considered in his calculation—the affluence of the parents, whether or not they were smokers, their general health—would also have to be considered in calculating the statistical likelihood of murder. Those same factors made murder less likely, not more.

But that wasn't how the data was framed to the jury.

When Meadow made his proclamation—that the chances of two children dying of SIDS one year apart while living in an affluent home with non-smoker parents was 1 in 75 million—the jury and the public heard this as, "There is a 1 in 75 million chance that Sally Clark is innocent."

In other words, it seemed that Sally had a better chance of dying in a terrorist attack on an airplane than of being innocent of this crime. 

The problem is, that wasn't what the data was saying.

Meadow's number wasn't a calculation of the odds of Sally's guilt. He had calculated the odds of two children dying from SIDS a year apart. Set aside for a moment that the calculation itself was faulty—even if it had been accurate it was being flat-out misused

Sir Meadow, by the way, was immortalized by having a legalistic philosophy named in his honor. Meadow's Law is based on a statement by Meadow, who said,"One is a tragedy, two is suspicious and three is murder unless there is proof to the contrary."

Meadow was one of the leading pediatric doctors in the UK. He was knighted. He had a law named for him. And he was dead wrong.

Sally Clark did not kill either of her children, which was determined by the court only after she'd served three years in prison for the crime. During her time in prison, she had a very rough go of it. Child killers aren't treated well inside. And so, for three years, she had to endure not only the loss of her children and the ruin of her former life, she also endured the constant verbal and physical abuse of fellow prisoners. 

When she was released in 2003, the damage to her psyche was already done. Her husband told the press that she would never be well. She was suffering from numerous psychological issues, including a complete personality change brought on my trauma. She eventually drank herself to death—dying from alcohol poisoning in her home at the age of 42.

The power of expert testimony

So what happened here? How was it that Meadow, renowned in his field and truly an expert in pediatrics and identifying abuse, could get this so completely wrong? And why did the jury trust him so completely?

That is the danger that accompanies any expert testimony in court, and it lends a great deal of weight to the argument that our current trend toward expert and authority businesses could be destructive. When events such as these happen, we can't help but question the whole system, and the lack of accountability that comes with certain forms of expertise.

We've learned through this deep dive, so far, that expertise is about credibility as much as it is about knowledge and know-how. When we are unsure of what we should do or think or decide, we look for someone we can outsource those decisions to. We trust people who have credentials we don't have, or who demonstrate knowledge on topics we don't understand.

Just as with our trust of financial experts, we are constantly looking for signs of credibility in others, so we can hand over the responsibility of a decision without worry. We trust the CPA to be good with numbers. We trust the dietician to give us good advice about food. We trust the knighted Professor of Pediatrics with a law name for him to know what he's talking about when he quotes a statistic. 

But it's that tendency that creates the biggest danger. We are concerned about our own lack of insight, and so we trust the insight of anyone who seems to know more than we do, which effectively causes us to shut off our analytical brains and just go with what we're told. It's easier. It feels safer. It can put an innocent woman in prison for three years, and ruin countless lives. 

Blue cars at night

"There are three things that make someone an expert," says Jim Moriarty, a prominent attorney in Houston, Texas. "Data, information and wisdom."

"Data is is the facts—the basic building material. It's like atoms. It isn't the castle, simply the building materials. Information is the facts combined with context. 'Blue' is data. It's nothing by itself, but 'the blue car runs a light at night' is information.

"Wisdom is the foundation for being an authority. It's the correct data with the correct insight. 'The blue car always runs that light at night, so the pedestrian should avoid that intersection at night when the blue car is around.' When you know the facts and you put them in context, and you draw your conclusions from that, you're an expert."

Jim has made a study of experts, because they can often be vital to building his cases. He tends to take cases that have large social benefit, and  to help people or solve problems that are being ignored by the rest of society.

His latest case is an attempt to change the laws and regulations surrounding corporate-owned-and-operated dental clinics. The practice is already illegal, but loopholes allow these facilities to keep operating. Worse, because they are able to charge Medicaid, the services often mask their operations as being part of a service to the community. Abuse runs rampant as these practices perform countless medically unnecessary dental procedures on children living at the poverty level, rushing them through an assembly-line-style process that causes far more harm than good, and collecting millions of dollars each year in government reimbursements. 

Jim's philosophy for finding experts differs greatly from that used by most attorneys. He doesn't pay for them, for starters.

As it turns out, it's legal to pay experts for their testimony, and the rates can be extremely high. 

"I've paid as much as $2 million for expert testimony, and it was a big scam. They try stretched things out to keep the money coming, and didn't produce anything worthwhile."

So to avoid this, Jim uses a technique straight out of "the Art of War." He gets the other guy's experts to do his work for him.

"I figure out the truth, and then I present it to their experts. I ask them, 'Is this how it works? Is this true?' And they're experts. They can't deny what they know while on the stand. So they say, 'Yes, that's how it works. That's true.'" 

In other words, Jim use the experts to verify the information—the data in context—that he already knows. He relies on their wisdom, under oath, and effectively lets the other side foot the bill for the expert testimony that wins his case.

That tactic works, but only if we keep to some simple rules:

  1. We have to look for the facts ourselves, and find their relevant context
  2. We have to ask the right questions to verify the information we have

Blinded by expertise

That was the real failure in the case of Sally Clark. Her attorneys, in the face of the overwhelming credibility of Sir Meadow, failed to look for the facts or ask the right questions. They failed to raise a flag on the dubious calculations. Above all, they failed to differentiate for the jury the concepts of the odds of two children dying from SIDS under those conditions versus the odds of Sally Clark's innocence

We've already learned that with expertise and authority comes great responsibility. As experts ourselves, we have to remember to be humble in our reach. We can't just assume that because we are considered an expert, we know everything we ever need to know on a subject.

Likewise, as we seek out the counsel of experts, we have to assume responsibility there as well. Trusting an expert has to come after we've vetted what we can of the facts and the information at hand. Basically, responsible use of an expert is to verify or elaborate on the facts you discover for yourself. An expert can be a source of new information, but it's up to us to investigate and verify that information as much as possible before acting on it. 

Sally Clark's life was ruined because of the testimony of a very credible source. He was considered wise by all. He was the unquestionable authority in his field. But he was wrong. And the price of that was the life of a woman who had already lost so much. 

As tragic as this outcome may be, however, it doesn't change our definition of expertise. In fact, it reinforces it—albeit with a cautionary tale attached. We are experts when we are recognized as such. But the credibility and prestige that come with that title also come with the weight of responsibility.

And, as it turns out, that responsibility is on the shoulders of the those seeking the expert's wisdom, as much as on the expert himself. 

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Kevin Tumlinson is the author of numerous novels, novellas, and non-fiction books, and the host of the Wordslinger Podcast. Try three of his best books for free when you download his starter library at


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